Patent GB-108328-A (GB)
Title: Improvements in or relating to Apparatus for Engraving or Sinking Dies and the like.
IPC: B23C3/20
Filed: 1916-05-01
Abstract: 108,328. Vickers, Ltd., and North, T. K. May 1, 1916. Engraving.-Relates to apparatus for engraving or sinking dies and the like, particularly of the kind in which tracing and cutting devices and movable tables are employed whereby the dies can be reproduced from a templet, pattern or model, and comprises a vertically reciprocating carriage having horizontally pivoted thereto, and extending upwardly therefrom, an arm or structure equipped with tracing and cutting devices for the model and work respectively, white the model and work are supported on tables adapted to be fed transversely at the proper times, relatively to the tracing and cutting devices. Fig. 1 is a front elevation of the apparatus and Fig. 3 is an end elevation looking in the direction of the arrow B, in Fig. 1. The bed b supports the main framework a and also carries an electric motor c adapted through the medium of a worm d and worm-wheel e, speed-reducing gear f controlled by an axially movable shaft g connected to a pivoted hand lever h, bevel-wheels i, a reversing-clutch device j and spur gears, to rotate in either direction a vertical lead-screw m engaging a nut on a carriage o which is thereby vertically reciprocated on guides o<x>. Pivoted to the carriage o, by horizontal adjustable centre pins n<x> in axial alinement, is a swinging arm or frame q having bearings r, r, and s carrying spindles t, t, and u for the cutting and tracing devices respectively. These spindles are rotated simultaneously by an endless belt v from the motor pulley w passing over pulleys x, x and tensioned by self-adjusting jockey pulleys y, y, on a spring- controlled pivoted arm z. The carriage o and swinging frame q are reciprocated vertically either automatically or by hand, by aid of adjustable trips c' near the top and bottom of the frame q which actuate a controlling rod d' by means of a lever e<1> in engagement with two set-screws on lugs on the rod d'. The rod d' is connected to the reversing clutch gear j by a pivoted lever j<1>. A doublearmed lever k<1> for hand controlling the reciprocating carriage o is connected to the controlling-rod d', and the clutch j may be maintained temporarily in an inoperative position by a locking cam m<1> and cam block n in conjunction with the hand-lever k. The depth of cut may be regulated by a hand-operated screw-threaded spindle o<1> carried by a bracket p<1> on the arm q and co-operating with the carriage o. The cutting and tracing tools are held in contact with the work and model respectively by a spring r<1> connected to the swinging frame q and the carriage o, the tension being regulated by a hand-wheel s<1> and screw s<x>. The carriage o and swinging frame q are counterbalanced by a weight connected thereto by a cord guided round pulleys, the weight having wheels to run on guide-ways cast on the framing a. Tables y<1>, z<1> having nuts for engagement with right and left threaded portions of an horizontal lead-screw a<11> respectively support the model and the work, the tables being moved horizontally by a " slow " or " fast " hand-operated feeding means or by automatic feeding means which can also be controlled by hand if desired. The " slow " hand feed is obtained by a hand-wheel 3" adapted through bevel-gearing c" and spur pinion d" to actuate a spur-wheel e" keved to the table leadscrew a<11>, while the " fast " band feed is effected by a hand-wheel f" secured direct to the leadscrew a<11>. The automatic feed may be derived from the lead-screw m by helical gears driving a shaft i<11>, near the outer end of which is freely mounted an angularly movable pawl-carrier j<11> provided with two pawls. These pawls are carried by a retaining ring and have projections to engage cams m<11>, m" carried by a movable but non- rotatable sleeve which is engaged by a spring tending to force the sleeve against the action of a trip stud and of a pivoted lever r<11> which, co-operating with the table z' maintains temporarily the sleeve so that the spring is compressed. When the automatic-feed i" rotates, one of the pawls actuates the pawl-carrier j<11> until the said pawl is disengaged from the driving-member by its cam m<11> on the sleeve. On reversal of the feed-shaft i<11>, the other pawl engages and actuates the pawlcarrier j<11> until disengaged by its corresponding cam m<11>, these cams m<11> being angularly adjustable so that the amount of feed can be regulated. The pawl-carrier j<11> is adapted to feed the table lead-screw a<11> by means of a rod u<11> connecting it to a lever t<11> carrying a pawl v<11>, which during the movement in one direction, actuates a ratchet wheel w<11> secured to the table lead-screw a<11>. The sleeve may be released by trip dogs so that the pawls are rendered inoperative. The automaticfeed shaft i<11> may also be actuated by bevel-gearing y<11> from a hand-wheel z<11>. In order that right-hand impressions may be cut from righthand models or left-hand impressions from lefthand models, the tables y<1>, x<1> can be coupled together, and one of the lead-screw nuts disengaged. This disengagement may be effected automatically by tho action of the table z<1>, when the tables are being brought together, on a spring- pressed cam pin b<111> carried bv the table y<1>. When the tables are disconnected, the nut re-engages with the lead-screw so that they will be driven in opposite directions as alreadv described. Lubricant for the cutting-devices may be supplied from a reservoir supported on a column above the work table.